Sprint announced that it intends to keep its unlimited data plans around awhile in order to have a competitive edge against AT&T, Verizon and T-Mobile -- which have eliminated their unlimited data.

At the GigaOm's Mobilize conference in San Francisco yesterday, Sprint Chief Technology Officer Stephen Bye expressed the company's commitment to unlimited data, calling it a "differentiator" from other U.S. carriers, according to Engadget.

But it's not enough to just be different. There is a high cost for supporting these subscribers and there's market pressure associated with maintaining unlimited services. Bye said he understood these costs, but defended unlimited plans by acknowledging that not every unlimited subscriber uses as much data as the next. He added that unlimited data plans are easier to maintain because there's no tiered data support or hidden costs for customer care.

However, launching a 4G network may be an issue with Sprint's current plan, considering the expense involved in maintaining such a network. According to CNET, Sprint will first have to eliminate its IDEN network and instead use that network's budget for data usage.

In addition, Sprint's upcoming acquirement of the iPhone 5 will put its unlimited data to the test, considering it will strain the carrier's capacity to hold on to these plans.

"Is there pressure? Yeah," said Bye. "There's a challenge for all engineers to work on how we get the cost structure down."